Reference is made to FIGS. 1 to 2. FIG. 1 is a schematic view showing the structure of a typical bogie, and FIG. 2 is a side view of the bogie shown in FIG. 1.
A bogie is an important structure in a railway vehicle, and uses two-stage suspension device, i.e., an axle box suspension positioning device 500 and a center suspension positioning device 400, for transmitting a load caused by the interaction between a vehicle body and a wheel track. The vehicle body mainly includes a frame 100, a swing bolster 200, a wheelset 300, and an axle box 600, etc. The load caused by the frame 100 and above is transmitted by the axle box suspension positioning device 500 to the wheelset 300 and finally to a steel rail. Each of the suspension devices has positioning rigidities in three directions, i.e., a vertical direction, a longitudinal direction and a transverse direction. A reasonable matching of the transverse positioning rigidity and the longitudinal positioning rigidity of the axle box suspension positioning device 500 is an important insurance for a vehicle to run stably in a straight line at high speed and safely in a curved line.
When a vehicle runs in a straight line at a high speed, the axle box suspension positioning device 500 is required to have a relatively large longitudinal positioning rigidity to counteract a snaking motion of the wheelset 300. A relatively large transverse positioning rigidity can also counteract the snaking motion of the wheelset 300 in a certain degree, but having less effect than the longitudinal positioning rigidity. When the vehicle runs in a curved line, both of the transverse positioning rigidity and the longitudinal positioning rigidity should not be too large, since an attack angle of the wheelset is required to be decreased and the wheel flange wear and the noise of the wheel and rail are required to be reduced as much as possible. Considering the running performance of the vehicle in a straight line and a curved line, the axle box suspension positioning device 500 should be designed to have a relatively large positioning rigidity, in particular a large longitudinal positioning rigidity.
Reference is made to FIG. 3, which is a schematic view showing the structure of a typical axle box suspension positioning device.
The axle box suspension positioning device 500 mainly includes a guide column assembly 510, an axle box spring 501, and a rubber positioner 502, etc. The guide column assembly 510 mainly includes a guide column 503, and further may include other components connected to the guide column 503, such as an anti-loose suspension seat 504, a bolt 505 for connecting the guide column 503 to the anti-loose suspension seat 504 as shown in FIG. 3. The guide column assembly 510 bears the load on the frame 100, and transmits the load to the axle box 600 via two paths, i.e., the axle box spring 501 and the rubber positioner 502. During the converting process from an empty loaded condition to a heavy loaded condition, the guide column assembly 510 moves as the axle box spring 501 moves, and has a possibility to extend out of the axle box 600. Thus, the axle box 600 has an opening for allowing the guide column assembly 510 to extend out, and the guide column assembly 510 has a free end which is extendable and retractable from the opening of the axle box 600. For the guide column assembly 510 only having the guide column 503, the free end of the guide column assembly 510 is just an end of the guide column 503.
Reference is made to FIGS. 4 and 5. FIG. 4 is a schematic view showing the state of the axle box suspension positioning device shown in FIG. 3 in an empty loaded condition. FIG. 5 is a schematic view showing the state of the axle box suspension positioning device shown in FIG. 3 in a heavy loaded condition.
As shown in FIG. 4, in the empty loaded condition, the load is relatively small, the rubber positioner 502 is stretched upwardly by the axle box spring 501. As shown in FIG. 5, in the heavy loaded condition, the load is relatively large, and both of the axle box spring 501 and the rubber positioner 502 are compressed downwardly simultaneously. The axle box suspension positioning device 500 is provided with the axle box spring 501 and the rubber positioner 502, which facilitates improving the static deflection of the empty vehicle, and reducing the difference of the deflections of between the empty vehicle and the heavy loaded vehicle, and improving the dynamic performance of the vehicle.
In addition, the opening of the axle box 600 should be in a relatively large size to avoid the guide column assembly 510 colliding with the axle box 600 when the guide column assembly 510 rotates with respect to the frame 100, thus, the guide column 510 and the axle box 600 are rigidly positioned, allowing a safety operation of the vehicle.
However, the axle box suspension positioning device 500 has the following disadvantages.
First, the guide column assembly 510 has a relatively small positioning rigidity, in particular under the empty loaded condition, thus the rubber positioner 502 is in a stretched state, and the safety of the vehicle in operation is reduced.
Secondly, in a case that the axle box 600 is rotated about the axle, the guide column assembly 510 is rotated simultaneously, thus the rubber positioner 502 is rotated, causing the rubber positioner 502 to be deformed, therefore the positioning rigidity, in particular the longitudinal positioning rigidity, is further decreased.
Thirdly, the deformation of the rubber positioner 502 may further generate bending moment to the guide column assembly 510, causing the guide column assembly 510 into a state just like a cantilever, in which the fixed end is the joint of the guide column 510 and the frame 100, thus a root portion of the guide column assembly 510 will suffer a poor stressed condition, which is bad for the structure, reducing the service life of the guide column assembly 510.
Therefore, a technical problem to be solved by the skilled person in the art is to provide an axle suspension positioning device 500 which has a relatively large positioning rigidity, a better stressed condition, and therefore a prolonged service life